Why is desalination bad?

Desalination has very high energy requirements and since most countries with desalination plants do not have nuclear power, it results in the burning of lots of more coal. Additionally, the methods by which salt is removed from water create a resulting "salt-slurry" which is ejected as waste in to the original saltwater body. This salt-slurry makes the area around the desalination plant poisonous for the local sea-life.

However, in almost every case, the positives of desalination outweigh these negatives.